“Normal” or so-called “euthymic” people are inclined to judge that hyperthymics/”optimists” view the world through rose-tinted spectacles. Their central information-processing system is systematically biased. Conversely, hyperthymics see the rest of us as unreasonably pessimistic. Chronic depressives, on the other hand, may view euthymic and hyperthymic people alike as deluded. Indeed victims of melancholic depression may feel the world itself is hateful and meaningless. For evolutionary reasons (cf. rank theory), a genetic predisposition to hyperthymia and euphoric unipolar mania are rarer than dysthymia or unipolar depression. Most of us fall somewhere in between these temperamental extremes, though the distribution is skewed to the southern end of the axis. Genetics plays a key role in determining our hedonic set-point, as does the ceaseless interplay between our genes and environmental stressors. Inadequate diet, imprudent drug use, and severe, chronic, uncontrolled stress can all reset an emotional thermostat at a lower level than its previous norm – though that norm may be surprisingly robust. Unlike recreational euphoriants, delayed-onset antidepressants may restore a lowered set-point to its former norm, or even elevate it. Antidepressants may act to reverse stress-induced hypertrophy of the basolateral amygdala and contrasting stress-induced dendritic atrophy in the hippocampus. Yet no mood-brightener currently licensed for depression reliably induces permanent bliss, whether information-signalling or constant, serene or manic. A genetically-determined ceiling stops our quality of life as a whole getting better.
Is the future of mood and motivation in the universe destined to be an endless replay of life’s evolutionary past? Are the same affective filters that were genetically adaptive for our hominid ancestors likely to be retained by our transhuman successors? Will superintelligent life-forms really opt to preserve the architecture of the primordial hedonic treadmill indefinitely? In each case, probably not, though it’s controversial whether designer drugs, neuroelectrodes or gene therapies will make the biggest impact on recalibrating the pleasure-pain axis. In the long-run, perhaps germline genetic engineering will deliver the greatest global enhancement of emotional well-being. For a reproductive revolution of designer babies is imminent. Thanks to genomic medicine, tomorrow’s parents will be able to choose the genetic make-up and personality of their offspring. Critically, parents-to-be will be able to select the emotional dial-settings of their progeny rather than play genetic roulette. In deciding what kind of children to create, tomorrow’s parents will (presumably) rarely opt for dysfunctional, depressive and malaise-ridden kids. Quite aside from the ethical implications of using old corrupt code, children who are temperamentally happy, loving and affectionate are far more enjoyable to bring up.
The collective outcome of these individual parental genetic choices will be far-reaching. In the new era of advanced biotechnology and reproductive medicine, a combination of designer drugs, autosomal gene therapies and germline interventions may give rise to a civilisation inhabiting a state-space located further “north” emotionally than present-day humans can imagine or coherently describe. Gradients of heritable, lifelong bliss may eventually become ubiquitous. The worst post-human lows may be far richer than the most sublime of today’s peak experiences. Less intuitively, our superwell descendants may be constitutionally smarter as well as happier than unenriched humans. Aided by synthetic enhancement technologies, fine-textured gradients of intense emotional well-being can play an information-signalling role at least as versatile and sophisticated as gradients of emotional ill-being or pain-sensations today. Simplistically, it may be said that posterity will be “permanently happy”. However, this expression can be a bit misleading. Post-humans are unlikely to be either “blissed out” wireheads or soma-addled junkies. Instead, we may navigate by the gradients of a multi-dimensional compass that’s designed – unlike its bug-ridden Darwinian predecessor – by intelligent agents for their own ends.